On 28/02/2019 13:20, NY wrote:
"Rod Speed" wrote in message
...
One thing that I'm always surprised at with LED bulbs used as room
lights is how bright the dimmest setting is - it's probably too
bright to use as a night light so you can see your way to the loo at
night without the light keeping you awake as you try to get to sleep.

Thats not true of the Hue bulbs.

Actually I have seen this with Hue bulbs - both the fixed-colour and the
colour bulbs. I suppose it's a matter of personal preference how dim you
like the dimmest setting to be, but the dimmest that I have seen with
Hue is still fairly bright.

Given that LEDs are usually dimmed by altering the mark:space ratio
of a constant-frequency square wave, so the light is turned on for a
progressively shorter proportion of each cycler,

Thats not true of all dimmers.

Ah, do some of them simply reduce the current, as you would with
tungsten - though with more complicated electronics?

PWM does reduce the average current, they may even have a smoothing
capacitor.
They don't need the smoothing capacitor if they chop the supply fast
enough so you can't see the flicker.
I usually use a few kHz when dimming LEDs.